Process for concentrating liquids.



, UNITED STATES PATENT our-ieu -raul. KESTNER, or LILLnraANcE, AssIGNoB. 'ro Kns'rinz'al nveronaa'cn. comm, oF rHILADELrHIA, PENNsYLVaNrA,A A' CORPORATION 0F PENNSYLVANIA.

PROC-Ess ron coNcENTnAnNG LIQUIns.

Specification. of Letters Patent.

original application lednlly 2o, icio, serial No.- sf/yass's. Divided and this appucntibnilled August' le.

1911. serialno. s44,4o5 l To aZZ whom #may concern.'

Be itV known that LPAUL KESTNER, a citizen of the Republic. of France, and a resi- 'dent 01CV Lille, Department Nord, France, "have invented certain Improvements 1n Processes for Concentrating Liquids, (being a division of my. application for patent tiled 4July 20, 1910, under Serial No. 572,855,

which is a division of myapplication filed November-1, 1909, Serial No. 525,710,) of

which the following is a specification.

My invention relates to a process of evapject of my invention is to provide-improved means for feeding' such liquid 'or `llqu-ld `bodies to the base of vertical tube evaporators in which concentration or evapora-' t-ion is effected bv the climbing ofthe liquid wit-hin elongated tubes externally heated v that will insure aneven and simultaneous feed of the liquid orqliquid bodies thereto.

' ward in this mannerby the presence of a.

In modern types of evaporatoratheliquid to be evaporated is usually conducted as'a tlln o r layer traveling over or through eling through a heated tube, it is necessary7 to providespeclal means for an even annu'- lar. distribution of the liquid upon the miler walls of the tube, and' since most of these evaporators use a plurality of `parallel tubes vheated by a'vcommon steam jacket and having a c ol'nlnoii feed, it is necessary to provide special means whereby the distribution of known as the'climbingfilinor Kestner type, the liquidis caused to travel upwardas an annular film through'a heated tube or series of tubes; It is caused to' travel upf central. body or core of steam or vapor p assing upward in contact with 1t and with con? siderable velocity. As actually manufactured, in this Kestner type of apparatus,

l, there is a plurality-0f parallel vertical tubes surrounded 'by a common steam Jacket. At.

their lower ends, these tubes pass through a horizontal. tubesheet into a feed chamber,

the ends. of the t-ub'es depending into this feed. chamber for some distance, say several inches. Into this' chamber 1s led liquid.

Without some such arrangement ullet whencoming in under less force. A';

`receive' thesalne relative amounts-,of liquid 'and vapor as each other tube. For-thlspur- This liquid when coming froma. -preyious effect and therefore relatively '-hot, jor when coming from a special preheater, n. enter# ing the feed chamber, undergoes self-eva ration, some or 'muchofits Water flashing;- into vapor. Thevaporiandfliquid passupward .through the heated -tlibeatheliquld' traveling upon theinner Wall ofthe'tube as "an annular layer, while thev vapor4 through the center ofthis4 annulus. In order to secure .an evendilst-ributionfof the liquid and' vapor. among 4x.the several' tubesand to insure each tubesecuringthe same relative amounts of liquid'andof 'va por, the depending ends of the tubes are pio vided'. with laterally presented orifices; ythe A'10 'lower ends being lslotted orbeveledf'as the v case may be.

The hot' liquid 'entering the feed chamber 'separates into vapor' .and liquid, the ,vapor layeroverlyingthe liquid i l`ayer. The laterally presented orifice- 4at 75 the base of4 thevtube prolongations taps-.both the liquid and 'the vapor layers, insuring that some 'of each-,shall enter'- 'ach' tube.

-this',- th.e tubes areaptto receive liquid .and vapor 8o alternately, or some of the tubes f'may"1"e:

ceive more liquid than othei's;'some`jof t he tubes may indeed. be dry; taking. nothing' but vapor, while other'tubes maybe-entirely A filled .with liquid. This is undesirable.: 'It J85 is, however, `somewhat difficult-.to produce a uniform level ofthe liquid to such va feed chamber'as described. Since 'the multiple effect'is Working under di'ferenti'al pressure Vand the'entering liquid comes into the effect l'9(1 under relatively high pressure, itentersrthe feed chamber with 'considerable velocity and tends to bank up more orless at. one point or another within such chamber.. It lnay,

for instance, iftlle inlet be somewhat itan- 95 gent-ial, pass around to 'the opposite "side of the chamber and there bank up", giving -a height of'liqui'd hivher'than that,nelft' the inlet.A Or thev liquid-may bank up. near-the In the presentinvention,'I have deviseda process of securing the desired even'feed of bothliquid and`vapor to-the 'several tubes and'for insuring that each such tube 'shall *I pose, I produce apreliminary 'separatipn-'bt vapor and of liquid in aspecial preliminary chamber and' then feed the. vaporseparated andthe liquid separated individually into the feed chamber proper 'of ,theapparatus And inthe v modification of my invention at present preferred, I `further introduce vthe oryapoif into, each tube as positive ]et, .drawing in the liquid after it' by what Abca-termed auf-injector action.'- Where is.: done-,the prolongation of the tubes is applicable to any type of evaporator .wherein an annular traveling Vlayer of liquid is produced on the interior of a heated tube, in its present speciticembodiment I regard' it -as more 'particularly applicable to "vaporators of thev stated Kestner or fclimbingilm type. i

' useful in 4the performance of .the stated.

body to all of the tubes simul- 6 working under vacuoor under ressure, the- In the. accompanying drawing, I have shown more 'or less diagrammatically certain organizations of apparatus elements withn iii the limits of the present invention and I'n this drawing: Figure 1, is a sectional -elevation of. one form of apparatus em-l bodying my' invention Fig. 2, is asectiona'l plan view of the same; Fig. 3, is aview similar to Fig. -1, of amodified construction .embodying my invention', and Fig. 4, is a sectional plan view of the structure shvvn injFig. .3.

Inthev operationof the elongated vertical tube evaporators of the said Kestner' t'pe inwhich evaporation is 4effected by lm '.climbing of theliquid or liquid body under ei1t,ftheessential result to be. obis,'as stated, the feeding of said liqbtane'ouslyland uniformly. T he liquid comfromir. revious evaporator is super-` heatedftliiitis, it is higher in temperature than theloiling point of the evaporator in hich tisintroduced, and the result is thatl ,fthe-instant 4the liquid passes the f eedvalye, the pressure being reduced, tlie boiling-point is reduced also and some ofthe liquid ,into steam, causing the liquid to befilled fwith bubbles i Y In multiple effect evaporators, whether nelativepressure in each succee Jing eectis 'always' lower than in the next preceding effect land, concomitantly, the boilin point f the li uidn assin' 4successively vt rfouhv o q p is glso lowered `so that-tile.

the several effects vapors from the 'preceding effect shall a Ways be hot enoughto boil the liquid in t] next succeeding edect. The liquid in pas ing from one eiiectinto the lower pressu of the next becomes partly vaporized and full of bubbles` of released steam. 4It is vei desirable that these bubbles of steam shoul be separated and separately introducedfin the tubes for ascent and evaporation therei One reason for this is that itis desirable have a uniform liquid level nearthe en of the tubes so that the' feed in eachvtul will be uniform; the steam entering tl tube independently of the liquid, at the t( of ajlaterally presented orifice or slot Whe sucharrangemen'tis provided, and the li uid entering the slottherebelow and passii up the tube adjacentthe walls of the san If thislevel is not made uniform, or if the is a' disturbance caused by the liquid ente ing'at one side of the feed chamber, it iv' be readily understood that some of the tub are apt to receive more liquid t-han others', condition that would interfere with the ei ciency of the apparatus. Owing to the pre enceof the large amount of vapor, due

a fallin temperature and pressure when t liquid is passed from one effect tothe fe chamber 'of the next effect, there is alWa] Aan opportunity for some'of the tubes to i ceive a greater amount of liquid th:

others; and the essential object of -myi vention is to provide a process whereby t liquid and its accompanying vapor may so controlled that the entrance ofthe sai ,tothe several tubes will take place simi taneously and ivitlia substantially unifor body of liquid and vapor.

In'the present embodiment of my inve tion, provision is made for definitely sep rating the liquid or liquid body from t steam or. vapor which accompanies it pri to -entering the feed chamber. To accoi -plish this, a separate chamber is provid disposed adjacent the feed chamber which in direct communication with the tubes, ai provision is made for independent .transf of the liquid and the steamy or vapor to sa feed chamber and the tubes in communie tion therewith.

' The forms of feedingrdevice shown ai described herein are designed to overcoi difficulties" heretofore met 'with in feedii liquid or liquid bodies undergoing treatme to the base of evapoiating tubes.

In Figs.- 1 and 2, of the drawings-hei "WithT-l-represents the lower. portion o f heating shell or casing Shown as f t .climbing'ilm type and'containing eva orating tubes2 to which the liquid 'orliqu body tolbeconcentrated is to be fedfor z cent therein. Carried by the shell or casii 1 is a tube sheet 3 to which the tubes a connected, while in the structure'shoivn Fia'sl and 4, the tubespassthroiigh sa v-tubeisliee-t'into' afeed chamber 4C, vand in such instance the tubes may be .beveled or s provided With laterally presented orifices or slots 5, in the manner. indicated in my prior Patent-N0.' 882,322. e

Referring again to Figs. l and 2, 7 repre- *sente a chamber disposed adjacent lthe casing 1,-and into which the heated liquid to be concentrated is fedfrom a suitable inlet S, and in which chamber more or less perfect separa-l tion of the steam -or vapor from the liquid kmay be effected; such steam or vapor being passeddirec'tly to the evaporating tubes 2'. For th1s'purp0se the chamber 7 has a passage. 9 for delivering the liquidto the chamber 4 belovv the tubes' and indirect commu-` nicationtherewith-,and a passage 10 With an inlet conduit llat the top of the cham! '4ber 7, which passage communicates with a chamber 12'belov'v said chamber 4, and. fromA this chamber 12 the steam or vapor may enter' thev evaporating` tubes 2 Ithrough short sections of tubing indicated at 13. In this form of ,thestructura no provision is made 'for extending the tubes Qinto the feed cham- 4 ber, butsucharrangement is- .not thought to be necessary AWith this particular structure in view of the direct means`used for 'trans ferring the steam or vapor to the evaporating tubes.-

' l f. yIn the structure shown inv Figs. 3 and el., the liquid enters an auxiliary. chamber 7a an'd'flowsthrough a passage la to the feed vchamber 4 .into which the evaporating tubes 2 proj-ect andstrikes a deilector or baille 1'5 therein, which serves to spread the liquid to all parts .of said chamber. The steam or vapor accompanying the liquid or developed Withinsaid chamber 7a rises to the top of the same and enters the feed chamber l through a passage 16 Which leads from a .point near the top of said chamber 7a and circulates around the upper portion of the feed chamber 4 simultaneously with the. entry of the liquid therebelow and With the latter wetting the inner Walls of the tubes 2 uniformly and simultaneously; it facilitates th'e'flow of liquid therein, and the op,` eration in the subsequent concentrationof" the same. v

With. the projecting tubes, the laterally l presented orifices 5 Will tap both steam and `liquid-layers, allowing a simultaneous entry of both into each tube, but with the structure of Fig. l, positive means are provided` for the delivery of liquid and of vapor into each evaporating` tube and the beveling or slotting of the tube ends and their prolonga tion becomes unnecessary.

'j The structures shown ,herein as auxiliary,

to the evaporator may/besef sheet metal or Cast metal, or parts may be'ofsheetlmetal and parts of cast metal. The tubes 2 maybe projected into the feed chamber 4.- as indicated in the 'structure 'shown in Figs. 3 and 4, to any desired extent; the desirability of such extension depending in some measure upon the size and capacity of the evaporating element. The several feed chambers are provided with suitable drainage outlets 18 closed by plugs-or `other suitable devices, or-they. may be provided With valves 20. In addition, the feed chamber in each instance is so constructed and arranged and of such size Withrespect Etothe shell containing the evaporatng tubes that all of saidV tubes are accessible Whensaid feed-chamber or the vlower portion of the same is removed.

The feature of the present invention is the provision ofa process'empl'oying `auxiliary means exterior of the main 'feed chamber and in communication With the evapo-` rating tubes for the separation of .the steam feeding of said steam or vapor and of said liquid to the tubes. A

An evaporator with the auxiliary devices shown comprising means for effecting an4 even feed and distribution of the liquid may beused as a single evaporating effect oras any effect of a multiple effect system and it `or vapor from theliquid, and the separate may be operated under a pressure greater or less than that of the atmosphere. Any

number of similar effects of'thisl type may be arranged in amultiple effect system or one such effect may be arranged in vcombi-` nation ivith effects of a different type. It

should, however, in Whatever arrangement. it be used, be so arranged as to receive a'supply of liquid at a temperature greater than the boiling point at the pressure prevailing in the effect so as to permit self evaporation` to take place in the preliminary chamber.

When used as a single effect or as the first effect of a multiple, is should therefore be coupled With a source of preheated liquid.

I claimgl. The process of evaporating liquids,v

vapor, separately conducting the vapor so formed and the residual liquid into difierent points of the feed chamber 'of an evaporator having heated tubes, and s1multanevously feeding portions of such liquid and of such vapor to each of said tubes. f 4. ln theevaporation of liquids,- the process vvhichcomprises 4releasing the pressure upon a heated liquid in a suitable ,chamber to permit self-evaporation and formationof vapor, separatelyl conducting the vapor so formed and the residual liquid into different points of the feed chamber of an evaporator having heated tubes, and simultaneously feeding portions of suchliquid and of such vapor to each of said tubes, the vapor being fed into the tubes in such manner as to draw in liquid by an injector action.

6. In the evaporation of liquids, lthe process which comprises releasing the pressure upon a vheated liquid in a suitable chamber to permit self-evaporation and formation of vapor, separately conduct-ing the vapor so formed and the residual liquid into different points of the feed chamber of an evaporator having vertical heated tubes, and simultaneously feeding portions of'such liquid and of such vapor to each of said tubes, the vapor being fed into the tubes in such. manner as to draw in liquid by an injector action.

7. The process, which consistsin separating a body of heated liquid into liquid and vapor; thereafter delivering the residual liquid to the feed chamber of aufilm evaporator; and facilitating the passage of the liquid to and through the tubes of the evaporator by means of vapor directed axially of the tubes.

8. The process, which consists vin relieving the pressure on a body ofheated liquid to form separate bodies of vapor and liquid, and causing the residual liquid tostart flowing upwardly through vertical .heated tubes by means of steam jets. l

9. The process which consists in relieving4 the pressure on 'a body of heated liquid to form separate bodies of liquid and vapor,

and starting the residual liquid to flow upwardly upon :the vvalls yof vvertical 'lleated tubes by means ofaxially directed jets. of

' vapor.

l0..The process, which consists 'in releasing the pressure on a heated liquid taper? mit of self-evaporation and formation of.v

vapor; separately conducting away vthe vapor so formed; delivering the 'residual liquid to the feed chamber' of a vertical tube evapo' rator; and delivering portions Ycf such liquid simultaneously to eachl of the tubes by means of vapor jetsv directedaxially ther-teinte.

il. vIn the evaporationy of liquids, the process which consists in releasingv the pressure upon a heated liquid ina suitable chamber to permit of self-,evaporation and formation of vapor ;'separately conducting away vapor so formed-and deliveringthe residual liquid into the'feed chamber of. an. evaporator having vertical heated: tubes; and simultaneously feeding portions ofsuch liquid to each of said tubes together with .a'jet of steam orl vapor directed axially' of the tubes to cause them to draw in liquidby an injector action.

12. 'The process which involves vleading heated liquid into a pressure releasing chamber to permit self-evaporationand formation of vapor; conducting away saidvapor; and transmitting the liquid soV treated-to the evaporating element 'of an evaporator Whose f prevailing temperaturel is less than that of said liquid.

13. In the evaporation of liquids', the proc-A ess which involves releasing the pressure upon a heated liqu'idin a suitable chamber to permit' of,selfev-aporation and formation of. vapor therefrom; 4separately conducting 1 away the vapor so formed; and delivering the residual liquid into the feed chamber of an evaporator having vert-ical heated tubes and operating at a temperature less than that of said liquid. y

I In testimony whereof, have signed myv nameto this specification, in' the presence of' ltwo subscribing Witnesses.

fPAUL KESTNER.

-VVitnesses' HENRI CH-ARRIER, LON Pacman. 

